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It doesn't >> change the behavior on 32-bit platforms. My understanding is that the >> issue surfaces only if there are too many PCIe controllers in the system >> which usually is the case in modern server systems and it is arguable if >> the server systems really run 32-bit kernels. > > Arguably people who do that can keep the pieces. > >> One way to fix it for both 32-bit and 64-bit systems is by changing the >> type of 'hwirq' to u64. This may cause two memory reads in 32-bit >> systems whenever 'hwirq' is accessed and that may intern cause some perf >> impact?? Is this the way you think I should be handling it? > > No. Leave it as is. What I'm asking for is that it's properly documented > in the changelog. Sure. I'll add this extra information in the change log. > > Thanks, > > tglx >